Rigorous

Webster's Dictionary of the English Language

·adj Violent.

II. Rigorous ·adj Severe; intense; inclement; as, a rigorous winter.

III. Rigorous ·adj Manifesting, exercising, or favoring rigor; allowing no abatement or mitigation; scrupulously accurate; exact; strict; severe; relentless; as, a rigorous officer of justice; a rigorous execution of law; a rigorous definition or demonstration.